Hi,
US government bonds, sometimes known as T-bills or treasury bills are generally taxed as income rather than capital gains.
The return is paid at maturity rather than regular interest payments.
In the UK, these are known as deeply discounted securities, with the discount being the difference between the price at which they were issued and the price received at maturity.
On a foreign investment the income is the difference between the purchase and redemption price after each has been converted to sterling on the day the transactions took place, so includes any foreign exchange gains. Losses cannot be deducted.
They are taxed as income. If you invest in deeply discounted securities, put the difference between what you paid for the bond and what you redeem or sell it for in box 3 of SA101 (page Ai1):
SA101
SAIM3010 for more information.
Accrued Income Scheme (Self Assessment helpsheet HS343), to determine if the AIS applies.
Thankyou.